منابع مشابه
Mephedrone: still available and twice the price.
In April, 2010, the β ketoamfetamine stimulant mephedrone (4-methylmethcathinone) and several similar compounds were classified as Class B substances in the UK under the Misuse of Drugs Act. Legislation was prom pted by public health concerns, with the expectation that these controls would limit availability and use. As part of our group’s ongoing research into new synthetic drugs, we did an on...
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A number of recent papers have addressed the algorithmic problem of allocating advertisement space for keywords in sponsored search auctions so as to maximize revenue, most of which assume that pricing is done via a first-price auction. This does not realistically model the Generalized Second Price (GSP) auction used in practice, in which bidders pay the next-highest bid for keywords that they ...
متن کاملA closer look at ‘Cheap White’ cigarettes
BACKGROUND Given the prominence of Cheap Whites in illicit tobacco discussions, we examined various definitions, market presence, brand proliferation, manufacturers, production locations, trademark ownership, prices and compliance with tax stamp and warning labels. METHODS Data from peer-reviewed and grey literature, newspapers, trademark registries, governments/international organisation rep...
متن کاملGoing Cheap: Determinants of Bird Price in the Taiwanese Pet Market
BACKGROUND International wildlife trade is the largest emerging source of vertebrate invasive alien species. In order to prevent invasions, it is essential to understand the mechanics of trade and, in particular, which traded species are most likely to be released or escape into the wild. A species' economic value is a key factor, because we expect cheaper species to be less assiduously secured...
متن کاملArcs on Spheres Intersecting at Most Twice
Let p be a puncture of a punctured sphere, and let Q be the set of all other punctures. We prove that the maximal cardinality of a set A of arcs pairwise intersecting at most once, which start at p and end in Q, is |χ|(|χ| + 1). We deduce that the maximal cardinality of a set of arcs with arbitrary endpoints pairwise intersecting at most twice is |χ|(|χ|+ 1)(|χ|+ 2).
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ژورنال
عنوان ژورنال: Chemical & Engineering News Archive
سال: 1961
ISSN: 0009-2347,2157-4936
DOI: 10.1021/cen-v039n044.p005